Btrfs: add validadtion checks for chunk loading
[sfrench/cifs-2.6.git] / fs / btrfs / volumes.c
index bd0f45fb38c462bf932462cfda57bcc2baac63cc..74507b05061b5aad1af8e568c5d347d5ec9a2153 100644 (file)
@@ -118,6 +118,21 @@ const u64 btrfs_raid_group[BTRFS_NR_RAID_TYPES] = {
        [BTRFS_RAID_RAID6]  = BTRFS_BLOCK_GROUP_RAID6,
 };
 
+/*
+ * Table to convert BTRFS_RAID_* to the error code if minimum number of devices
+ * condition is not met. Zero means there's no corresponding
+ * BTRFS_ERROR_DEV_*_NOT_MET value.
+ */
+const int btrfs_raid_mindev_error[BTRFS_NR_RAID_TYPES] = {
+       [BTRFS_RAID_RAID10] = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET,
+       [BTRFS_RAID_RAID1]  = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET,
+       [BTRFS_RAID_DUP]    = 0,
+       [BTRFS_RAID_RAID0]  = 0,
+       [BTRFS_RAID_SINGLE] = 0,
+       [BTRFS_RAID_RAID5]  = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET,
+       [BTRFS_RAID_RAID6]  = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET,
+};
+
 static int init_first_rw_device(struct btrfs_trans_handle *trans,
                                struct btrfs_root *root,
                                struct btrfs_device *device);
@@ -699,7 +714,8 @@ static noinline int device_list_add(const char *path,
         * if there is new btrfs on an already registered device,
         * then remove the stale device entry.
         */
-       btrfs_free_stale_device(device);
+       if (ret > 0)
+               btrfs_free_stale_device(device);
 
        *fs_devices_ret = fs_devices;
 
@@ -988,6 +1004,56 @@ int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
        return ret;
 }
 
+void btrfs_release_disk_super(struct page *page)
+{
+       kunmap(page);
+       put_page(page);
+}
+
+int btrfs_read_disk_super(struct block_device *bdev, u64 bytenr,
+               struct page **page, struct btrfs_super_block **disk_super)
+{
+       void *p;
+       pgoff_t index;
+
+       /* make sure our super fits in the device */
+       if (bytenr + PAGE_SIZE >= i_size_read(bdev->bd_inode))
+               return 1;
+
+       /* make sure our super fits in the page */
+       if (sizeof(**disk_super) > PAGE_SIZE)
+               return 1;
+
+       /* make sure our super doesn't straddle pages on disk */
+       index = bytenr >> PAGE_SHIFT;
+       if ((bytenr + sizeof(**disk_super) - 1) >> PAGE_SHIFT != index)
+               return 1;
+
+       /* pull in the page with our super */
+       *page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
+                                  index, GFP_KERNEL);
+
+       if (IS_ERR_OR_NULL(*page))
+               return 1;
+
+       p = kmap(*page);
+
+       /* align our pointer to the offset of the super block */
+       *disk_super = p + (bytenr & ~PAGE_MASK);
+
+       if (btrfs_super_bytenr(*disk_super) != bytenr ||
+           btrfs_super_magic(*disk_super) != BTRFS_MAGIC) {
+               btrfs_release_disk_super(*page);
+               return 1;
+       }
+
+       if ((*disk_super)->label[0] &&
+               (*disk_super)->label[BTRFS_LABEL_SIZE - 1])
+               (*disk_super)->label[BTRFS_LABEL_SIZE - 1] = '\0';
+
+       return 0;
+}
+
 /*
  * Look for a btrfs signature on a device. This may be called out of the mount path
  * and we are not allowed to call set_blocksize during the scan. The superblock
@@ -999,13 +1065,11 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
        struct btrfs_super_block *disk_super;
        struct block_device *bdev;
        struct page *page;
-       void *p;
        int ret = -EINVAL;
        u64 devid;
        u64 transid;
        u64 total_devices;
        u64 bytenr;
-       pgoff_t index;
 
        /*
         * we would like to check all the supers, but that would make
@@ -1018,41 +1082,14 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
        mutex_lock(&uuid_mutex);
 
        bdev = blkdev_get_by_path(path, flags, holder);
-
        if (IS_ERR(bdev)) {
                ret = PTR_ERR(bdev);
                goto error;
        }
 
-       /* make sure our super fits in the device */
-       if (bytenr + PAGE_SIZE >= i_size_read(bdev->bd_inode))
-               goto error_bdev_put;
-
-       /* make sure our super fits in the page */
-       if (sizeof(*disk_super) > PAGE_SIZE)
+       if (btrfs_read_disk_super(bdev, bytenr, &page, &disk_super))
                goto error_bdev_put;
 
-       /* make sure our super doesn't straddle pages on disk */
-       index = bytenr >> PAGE_SHIFT;
-       if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_SHIFT != index)
-               goto error_bdev_put;
-
-       /* pull in the page with our super */
-       page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
-                                  index, GFP_NOFS);
-
-       if (IS_ERR_OR_NULL(page))
-               goto error_bdev_put;
-
-       p = kmap(page);
-
-       /* align our pointer to the offset of the super block */
-       disk_super = p + (bytenr & ~PAGE_MASK);
-
-       if (btrfs_super_bytenr(disk_super) != bytenr ||
-           btrfs_super_magic(disk_super) != BTRFS_MAGIC)
-               goto error_unmap;
-
        devid = btrfs_stack_device_id(&disk_super->dev_item);
        transid = btrfs_super_generation(disk_super);
        total_devices = btrfs_super_num_devices(disk_super);
@@ -1060,8 +1097,6 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
        ret = device_list_add(path, disk_super, devid, fs_devices_ret);
        if (ret > 0) {
                if (disk_super->label[0]) {
-                       if (disk_super->label[BTRFS_LABEL_SIZE - 1])
-                               disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0';
                        printk(KERN_INFO "BTRFS: device label %s ", disk_super->label);
                } else {
                        printk(KERN_INFO "BTRFS: device fsid %pU ", disk_super->fsid);
@@ -1073,9 +1108,7 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
        if (!ret && fs_devices_ret)
                (*fs_devices_ret)->total_devices = total_devices;
 
-error_unmap:
-       kunmap(page);
-       put_page(page);
+       btrfs_release_disk_super(page);
 
 error_bdev_put:
        blkdev_put(bdev, flags);
@@ -1454,7 +1487,7 @@ again:
                extent = btrfs_item_ptr(leaf, path->slots[0],
                                        struct btrfs_dev_extent);
        } else {
-               btrfs_std_error(root->fs_info, ret, "Slot search failed");
+               btrfs_handle_fs_error(root->fs_info, ret, "Slot search failed");
                goto out;
        }
 
@@ -1462,7 +1495,7 @@ again:
 
        ret = btrfs_del_item(trans, root, path);
        if (ret) {
-               btrfs_std_error(root->fs_info, ret,
+               btrfs_handle_fs_error(root->fs_info, ret,
                            "Failed to remove dev extent item");
        } else {
                set_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags);
@@ -1688,32 +1721,92 @@ out:
        return ret;
 }
 
-int btrfs_rm_device(struct btrfs_root *root, char *device_path)
+/*
+ * Verify that @num_devices satisfies the RAID profile constraints in the whole
+ * filesystem. It's up to the caller to adjust that number regarding eg. device
+ * replace.
+ */
+static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info,
+               u64 num_devices)
+{
+       u64 all_avail;
+       unsigned seq;
+       int i;
+
+       do {
+               seq = read_seqbegin(&fs_info->profiles_lock);
+
+               all_avail = fs_info->avail_data_alloc_bits |
+                           fs_info->avail_system_alloc_bits |
+                           fs_info->avail_metadata_alloc_bits;
+       } while (read_seqretry(&fs_info->profiles_lock, seq));
+
+       for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
+               if (!(all_avail & btrfs_raid_group[i]))
+                       continue;
+
+               if (num_devices < btrfs_raid_array[i].devs_min) {
+                       int ret = btrfs_raid_mindev_error[i];
+
+                       if (ret)
+                               return ret;
+               }
+       }
+
+       return 0;
+}
+
+struct btrfs_device *btrfs_find_next_active_device(struct btrfs_fs_devices *fs_devs,
+                                       struct btrfs_device *device)
 {
-       struct btrfs_device *device;
        struct btrfs_device *next_device;
-       struct block_device *bdev;
-       struct buffer_head *bh = NULL;
-       struct btrfs_super_block *disk_super;
+
+       list_for_each_entry(next_device, &fs_devs->devices, dev_list) {
+               if (next_device != device &&
+                       !next_device->missing && next_device->bdev)
+                       return next_device;
+       }
+
+       return NULL;
+}
+
+/*
+ * Helper function to check if the given device is part of s_bdev / latest_bdev
+ * and replace it with the provided or the next active device, in the context
+ * where this function called, there should be always be another device (or
+ * this_dev) which is active.
+ */
+void btrfs_assign_next_active_device(struct btrfs_fs_info *fs_info,
+               struct btrfs_device *device, struct btrfs_device *this_dev)
+{
+       struct btrfs_device *next_device;
+
+       if (this_dev)
+               next_device = this_dev;
+       else
+               next_device = btrfs_find_next_active_device(fs_info->fs_devices,
+                                                               device);
+       ASSERT(next_device);
+
+       if (fs_info->sb->s_bdev &&
+                       (fs_info->sb->s_bdev == device->bdev))
+               fs_info->sb->s_bdev = next_device->bdev;
+
+       if (fs_info->fs_devices->latest_bdev == device->bdev)
+               fs_info->fs_devices->latest_bdev = next_device->bdev;
+}
+
+int btrfs_rm_device(struct btrfs_root *root, char *device_path, u64 devid)
+{
+       struct btrfs_device *device;
        struct btrfs_fs_devices *cur_devices;
-       u64 all_avail;
-       u64 devid;
        u64 num_devices;
-       u8 *dev_uuid;
-       unsigned seq;
        int ret = 0;
        bool clear_super = false;
+       char *dev_name = NULL;
 
        mutex_lock(&uuid_mutex);
 
-       do {
-               seq = read_seqbegin(&root->fs_info->profiles_lock);
-
-               all_avail = root->fs_info->avail_data_alloc_bits |
-                           root->fs_info->avail_system_alloc_bits |
-                           root->fs_info->avail_metadata_alloc_bits;
-       } while (read_seqretry(&root->fs_info->profiles_lock, seq));
-
        num_devices = root->fs_info->fs_devices->num_devices;
        btrfs_dev_replace_lock(&root->fs_info->dev_replace, 0);
        if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) {
@@ -1722,78 +1815,23 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
        }
        btrfs_dev_replace_unlock(&root->fs_info->dev_replace, 0);
 
-       if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
-               ret = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET;
-               goto out;
-       }
-
-       if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
-               ret = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET;
+       ret = btrfs_check_raid_min_devices(root->fs_info, num_devices - 1);
+       if (ret)
                goto out;
-       }
 
-       if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) &&
-           root->fs_info->fs_devices->rw_devices <= 2) {
-               ret = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET;
-               goto out;
-       }
-       if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) &&
-           root->fs_info->fs_devices->rw_devices <= 3) {
-               ret = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET;
+       ret = btrfs_find_device_by_devspec(root, devid, device_path,
+                               &device);
+       if (ret)
                goto out;
-       }
-
-       if (strcmp(device_path, "missing") == 0) {
-               struct list_head *devices;
-               struct btrfs_device *tmp;
-
-               device = NULL;
-               devices = &root->fs_info->fs_devices->devices;
-               /*
-                * It is safe to read the devices since the volume_mutex
-                * is held.
-                */
-               list_for_each_entry(tmp, devices, dev_list) {
-                       if (tmp->in_fs_metadata &&
-                           !tmp->is_tgtdev_for_dev_replace &&
-                           !tmp->bdev) {
-                               device = tmp;
-                               break;
-                       }
-               }
-               bdev = NULL;
-               bh = NULL;
-               disk_super = NULL;
-               if (!device) {
-                       ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
-                       goto out;
-               }
-       } else {
-               ret = btrfs_get_bdev_and_sb(device_path,
-                                           FMODE_WRITE | FMODE_EXCL,
-                                           root->fs_info->bdev_holder, 0,
-                                           &bdev, &bh);
-               if (ret)
-                       goto out;
-               disk_super = (struct btrfs_super_block *)bh->b_data;
-               devid = btrfs_stack_device_id(&disk_super->dev_item);
-               dev_uuid = disk_super->dev_item.uuid;
-               device = btrfs_find_device(root->fs_info, devid, dev_uuid,
-                                          disk_super->fsid);
-               if (!device) {
-                       ret = -ENOENT;
-                       goto error_brelse;
-               }
-       }
 
        if (device->is_tgtdev_for_dev_replace) {
                ret = BTRFS_ERROR_DEV_TGT_REPLACE;
-               goto error_brelse;
+               goto out;
        }
 
        if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
                ret = BTRFS_ERROR_DEV_ONLY_WRITABLE;
-               goto error_brelse;
+               goto out;
        }
 
        if (device->writeable) {
@@ -1801,6 +1839,11 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
                list_del_init(&device->dev_alloc_list);
                device->fs_devices->rw_devices--;
                unlock_chunks(root);
+               dev_name = kstrdup(device->name->str, GFP_KERNEL);
+               if (!dev_name) {
+                       ret = -ENOMEM;
+                       goto error_undo;
+               }
                clear_super = true;
        }
 
@@ -1842,12 +1885,7 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
        if (device->missing)
                device->fs_devices->missing_devices--;
 
-       next_device = list_entry(root->fs_info->fs_devices->devices.next,
-                                struct btrfs_device, dev_list);
-       if (device->bdev == root->fs_info->sb->s_bdev)
-               root->fs_info->sb->s_bdev = next_device->bdev;
-       if (device->bdev == root->fs_info->fs_devices->latest_bdev)
-               root->fs_info->fs_devices->latest_bdev = next_device->bdev;
+       btrfs_assign_next_active_device(root->fs_info, device, NULL);
 
        if (device->bdev) {
                device->fs_devices->open_devices--;
@@ -1883,63 +1921,23 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
         * at this point, the device is zero sized.  We want to
         * remove it from the devices list and zero out the old super
         */
-       if (clear_super && disk_super) {
-               u64 bytenr;
-               int i;
-
-               /* make sure this device isn't detected as part of
-                * the FS anymore
-                */
-               memset(&disk_super->magic, 0, sizeof(disk_super->magic));
-               set_buffer_dirty(bh);
-               sync_dirty_buffer(bh);
-
-               /* clear the mirror copies of super block on the disk
-                * being removed, 0th copy is been taken care above and
-                * the below would take of the rest
-                */
-               for (i = 1; i < BTRFS_SUPER_MIRROR_MAX; i++) {
-                       bytenr = btrfs_sb_offset(i);
-                       if (bytenr + BTRFS_SUPER_INFO_SIZE >=
-                                       i_size_read(bdev->bd_inode))
-                               break;
-
-                       brelse(bh);
-                       bh = __bread(bdev, bytenr / 4096,
-                                       BTRFS_SUPER_INFO_SIZE);
-                       if (!bh)
-                               continue;
-
-                       disk_super = (struct btrfs_super_block *)bh->b_data;
-
-                       if (btrfs_super_bytenr(disk_super) != bytenr ||
-                               btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
-                               continue;
-                       }
-                       memset(&disk_super->magic, 0,
-                                               sizeof(disk_super->magic));
-                       set_buffer_dirty(bh);
-                       sync_dirty_buffer(bh);
+       if (clear_super) {
+               struct block_device *bdev;
+
+               bdev = blkdev_get_by_path(dev_name, FMODE_READ | FMODE_EXCL,
+                                               root->fs_info->bdev_holder);
+               if (!IS_ERR(bdev)) {
+                       btrfs_scratch_superblocks(bdev, dev_name);
+                       blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
                }
        }
 
-       ret = 0;
-
-       if (bdev) {
-               /* Notify udev that device has changed */
-               btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
-
-               /* Update ctime/mtime for device path for libblkid */
-               update_dev_time(device_path);
-       }
-
-error_brelse:
-       brelse(bh);
-       if (bdev)
-               blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
 out:
+       kfree(dev_name);
+
        mutex_unlock(&uuid_mutex);
        return ret;
+
 error_undo:
        if (device->writeable) {
                lock_chunks(root);
@@ -1948,7 +1946,7 @@ error_undo:
                device->fs_devices->rw_devices++;
                unlock_chunks(root);
        }
-       goto error_brelse;
+       goto out;
 }
 
 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
@@ -1972,11 +1970,8 @@ void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
        if (srcdev->missing)
                fs_devices->missing_devices--;
 
-       if (srcdev->writeable) {
+       if (srcdev->writeable)
                fs_devices->rw_devices--;
-               /* zero out the old super if it is writable */
-               btrfs_scratch_superblocks(srcdev->bdev, srcdev->name->str);
-       }
 
        if (srcdev->bdev)
                fs_devices->open_devices--;
@@ -1987,6 +1982,10 @@ void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
 {
        struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
 
+       if (srcdev->writeable) {
+               /* zero out the old super if it is writable */
+               btrfs_scratch_superblocks(srcdev->bdev, srcdev->name->str);
+       }
        call_rcu(&srcdev->rcu, free_device);
 
        /*
@@ -2016,32 +2015,33 @@ void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
                                      struct btrfs_device *tgtdev)
 {
-       struct btrfs_device *next_device;
-
        mutex_lock(&uuid_mutex);
        WARN_ON(!tgtdev);
        mutex_lock(&fs_info->fs_devices->device_list_mutex);
 
        btrfs_sysfs_rm_device_link(fs_info->fs_devices, tgtdev);
 
-       if (tgtdev->bdev) {
-               btrfs_scratch_superblocks(tgtdev->bdev, tgtdev->name->str);
+       if (tgtdev->bdev)
                fs_info->fs_devices->open_devices--;
-       }
+
        fs_info->fs_devices->num_devices--;
 
-       next_device = list_entry(fs_info->fs_devices->devices.next,
-                                struct btrfs_device, dev_list);
-       if (tgtdev->bdev == fs_info->sb->s_bdev)
-               fs_info->sb->s_bdev = next_device->bdev;
-       if (tgtdev->bdev == fs_info->fs_devices->latest_bdev)
-               fs_info->fs_devices->latest_bdev = next_device->bdev;
-       list_del_rcu(&tgtdev->dev_list);
+       btrfs_assign_next_active_device(fs_info, tgtdev, NULL);
 
-       call_rcu(&tgtdev->rcu, free_device);
+       list_del_rcu(&tgtdev->dev_list);
 
        mutex_unlock(&fs_info->fs_devices->device_list_mutex);
        mutex_unlock(&uuid_mutex);
+
+       /*
+        * The update_dev_time() with in btrfs_scratch_superblocks()
+        * may lead to a call to btrfs_show_devname() which will try
+        * to hold device_list_mutex. And here this device
+        * is already out of device list, so we don't have to hold
+        * the device_list_mutex lock.
+        */
+       btrfs_scratch_superblocks(tgtdev->bdev, tgtdev->name->str);
+       call_rcu(&tgtdev->rcu, free_device);
 }
 
 static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path,
@@ -2101,6 +2101,31 @@ int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
        }
 }
 
+/*
+ * Lookup a device given by device id, or the path if the id is 0.
+ */
+int btrfs_find_device_by_devspec(struct btrfs_root *root, u64 devid,
+                                        char *devpath,
+                                        struct btrfs_device **device)
+{
+       int ret;
+
+       if (devid) {
+               ret = 0;
+               *device = btrfs_find_device(root->fs_info, devid, NULL,
+                                           NULL);
+               if (!*device)
+                       ret = -ENOENT;
+       } else {
+               if (!devpath || !devpath[0])
+                       return -EINVAL;
+
+               ret = btrfs_find_device_missing_or_by_path(root, devpath,
+                                                          device);
+       }
+       return ret;
+}
+
 /*
  * does all the dirty work required for changing file system's UUID.
  */
@@ -2165,7 +2190,7 @@ static int btrfs_prepare_sprout(struct btrfs_root *root)
 }
 
 /*
- * strore the expected generation for seed devices in device items.
+ * Store the expected generation for seed devices in device items.
  */
 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
                               struct btrfs_root *root)
@@ -2418,7 +2443,7 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
 
                ret = btrfs_relocate_sys_chunks(root);
                if (ret < 0)
-                       btrfs_std_error(root->fs_info, ret,
+                       btrfs_handle_fs_error(root->fs_info, ret,
                                    "Failed to relocate sys chunks after "
                                    "device initialization. This can be fixed "
                                    "using the \"btrfs balance\" command.");
@@ -2663,7 +2688,7 @@ static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
        if (ret < 0)
                goto out;
        else if (ret > 0) { /* Logic error or corruption */
-               btrfs_std_error(root->fs_info, -ENOENT,
+               btrfs_handle_fs_error(root->fs_info, -ENOENT,
                            "Failed lookup while freeing chunk.");
                ret = -ENOENT;
                goto out;
@@ -2671,7 +2696,7 @@ static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
 
        ret = btrfs_del_item(trans, root, path);
        if (ret < 0)
-               btrfs_std_error(root->fs_info, ret,
+               btrfs_handle_fs_error(root->fs_info, ret,
                            "Failed to delete chunk item.");
 out:
        btrfs_free_path(path);
@@ -2857,7 +2882,7 @@ static int btrfs_relocate_chunk(struct btrfs_root *root, u64 chunk_offset)
                                                     chunk_offset);
        if (IS_ERR(trans)) {
                ret = PTR_ERR(trans);
-               btrfs_std_error(root->fs_info, ret, NULL);
+               btrfs_handle_fs_error(root->fs_info, ret, NULL);
                return ret;
        }
 
@@ -3362,7 +3387,7 @@ static int should_balance_chunk(struct btrfs_root *root,
        } else if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)) {
                /*
                 * Same logic as the 'limit' filter; the minimum cannot be
-                * determined here because we do not have the global informatoin
+                * determined here because we do not have the global information
                 * about the count of all chunks that satisfy the filters.
                 */
                if (bargs->limit_max == 0)
@@ -3402,6 +3427,7 @@ static int __btrfs_balance(struct btrfs_fs_info *fs_info)
        u32 count_meta = 0;
        u32 count_sys = 0;
        int chunk_reserved = 0;
+       u64 bytes_used = 0;
 
        /* step one make some room on all the devices */
        devices = &fs_info->fs_devices->devices;
@@ -3540,7 +3566,13 @@ again:
                        goto loop;
                }
 
-               if ((chunk_type & BTRFS_BLOCK_GROUP_DATA) && !chunk_reserved) {
+               ASSERT(fs_info->data_sinfo);
+               spin_lock(&fs_info->data_sinfo->lock);
+               bytes_used = fs_info->data_sinfo->bytes_used;
+               spin_unlock(&fs_info->data_sinfo->lock);
+
+               if ((chunk_type & BTRFS_BLOCK_GROUP_DATA) &&
+                   !chunk_reserved && !bytes_used) {
                        trans = btrfs_start_transaction(chunk_root, 0);
                        if (IS_ERR(trans)) {
                                mutex_unlock(&fs_info->delete_unused_bgs_mutex);
@@ -3632,7 +3664,7 @@ static void __cancel_balance(struct btrfs_fs_info *fs_info)
        unset_balance_control(fs_info);
        ret = del_balance_item(fs_info->tree_root);
        if (ret)
-               btrfs_std_error(fs_info, ret, NULL);
+               btrfs_handle_fs_error(fs_info, ret, NULL);
 
        atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
 }
@@ -3693,10 +3725,8 @@ int btrfs_balance(struct btrfs_balance_control *bctl,
                num_devices--;
        }
        btrfs_dev_replace_unlock(&fs_info->dev_replace, 0);
-       allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
-       if (num_devices == 1)
-               allowed |= BTRFS_BLOCK_GROUP_DUP;
-       else if (num_devices > 1)
+       allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE | BTRFS_BLOCK_GROUP_DUP;
+       if (num_devices > 1)
                allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
        if (num_devices > 2)
                allowed |= BTRFS_BLOCK_GROUP_RAID5;
@@ -4200,6 +4230,7 @@ int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
        if (IS_ERR(uuid_root)) {
                ret = PTR_ERR(uuid_root);
                btrfs_abort_transaction(trans, tree_root, ret);
+               btrfs_end_transaction(trans, tree_root);
                return ret;
        }
 
@@ -5278,7 +5309,15 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
        stripe_nr = div64_u64(stripe_nr, stripe_len);
 
        stripe_offset = stripe_nr * stripe_len;
-       BUG_ON(offset < stripe_offset);
+       if (offset < stripe_offset) {
+               btrfs_crit(fs_info, "stripe math has gone wrong, "
+                          "stripe_offset=%llu, offset=%llu, start=%llu, "
+                          "logical=%llu, stripe_len=%llu",
+                          stripe_offset, offset, em->start, logical,
+                          stripe_len);
+               free_extent_map(em);
+               return -EINVAL;
+       }
 
        /* stripe_offset is the offset of this block in its stripe*/
        stripe_offset = offset - stripe_offset;
@@ -5519,7 +5558,13 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                                &stripe_index);
                mirror_num = stripe_index + 1;
        }
-       BUG_ON(stripe_index >= map->num_stripes);
+       if (stripe_index >= map->num_stripes) {
+               btrfs_crit(fs_info, "stripe index math went horribly wrong, "
+                          "got stripe_index=%u, num_stripes=%u",
+                          stripe_index, map->num_stripes);
+               ret = -EINVAL;
+               goto out;
+       }
 
        num_alloc_stripes = num_stripes;
        if (dev_replace_is_ongoing) {
@@ -6032,7 +6077,7 @@ static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
 {
        atomic_inc(&bbio->error);
        if (atomic_dec_and_test(&bbio->stripes_pending)) {
-               /* Shoud be the original bio. */
+               /* Should be the original bio. */
                WARN_ON(bio != bbio->orig_bio);
 
                btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
@@ -6206,27 +6251,23 @@ struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
        return dev;
 }
 
-static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
-                         struct extent_buffer *leaf,
-                         struct btrfs_chunk *chunk)
+/* Return -EIO if any error, otherwise return 0. */
+static int btrfs_check_chunk_valid(struct btrfs_root *root,
+                                  struct extent_buffer *leaf,
+                                  struct btrfs_chunk *chunk, u64 logical)
 {
-       struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
-       struct map_lookup *map;
-       struct extent_map *em;
-       u64 logical;
        u64 length;
        u64 stripe_len;
-       u64 devid;
-       u8 uuid[BTRFS_UUID_SIZE];
-       int num_stripes;
-       int ret;
-       int i;
+       u16 num_stripes;
+       u16 sub_stripes;
+       u64 type;
 
-       logical = key->offset;
        length = btrfs_chunk_length(leaf, chunk);
        stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
        num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
-       /* Validation check */
+       sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
+       type = btrfs_chunk_type(leaf, chunk);
+
        if (!num_stripes) {
                btrfs_err(root->fs_info, "invalid chunk num_stripes: %u",
                          num_stripes);
@@ -6237,24 +6278,70 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
                          "invalid chunk logical %llu", logical);
                return -EIO;
        }
+       if (btrfs_chunk_sector_size(leaf, chunk) != root->sectorsize) {
+               btrfs_err(root->fs_info, "invalid chunk sectorsize %u",
+                         btrfs_chunk_sector_size(leaf, chunk));
+               return -EIO;
+       }
        if (!length || !IS_ALIGNED(length, root->sectorsize)) {
                btrfs_err(root->fs_info,
                        "invalid chunk length %llu", length);
                return -EIO;
        }
-       if (!is_power_of_2(stripe_len)) {
+       if (!is_power_of_2(stripe_len) || stripe_len != BTRFS_STRIPE_LEN) {
                btrfs_err(root->fs_info, "invalid chunk stripe length: %llu",
                          stripe_len);
                return -EIO;
        }
        if (~(BTRFS_BLOCK_GROUP_TYPE_MASK | BTRFS_BLOCK_GROUP_PROFILE_MASK) &
-           btrfs_chunk_type(leaf, chunk)) {
+           type) {
                btrfs_err(root->fs_info, "unrecognized chunk type: %llu",
                          ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
                            BTRFS_BLOCK_GROUP_PROFILE_MASK) &
                          btrfs_chunk_type(leaf, chunk));
                return -EIO;
        }
+       if ((type & BTRFS_BLOCK_GROUP_RAID10 && sub_stripes != 2) ||
+           (type & BTRFS_BLOCK_GROUP_RAID1 && num_stripes < 1) ||
+           (type & BTRFS_BLOCK_GROUP_RAID5 && num_stripes < 2) ||
+           (type & BTRFS_BLOCK_GROUP_RAID6 && num_stripes < 3) ||
+           (type & BTRFS_BLOCK_GROUP_DUP && num_stripes > 2) ||
+           ((type & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 &&
+            num_stripes != 1)) {
+               btrfs_err(root->fs_info,
+                       "invalid num_stripes:sub_stripes %u:%u for profile %llu",
+                       num_stripes, sub_stripes,
+                       type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
+               return -EIO;
+       }
+
+       return 0;
+}
+
+static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
+                         struct extent_buffer *leaf,
+                         struct btrfs_chunk *chunk)
+{
+       struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
+       struct map_lookup *map;
+       struct extent_map *em;
+       u64 logical;
+       u64 length;
+       u64 stripe_len;
+       u64 devid;
+       u8 uuid[BTRFS_UUID_SIZE];
+       int num_stripes;
+       int ret;
+       int i;
+
+       logical = key->offset;
+       length = btrfs_chunk_length(leaf, chunk);
+       stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
+       num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
+
+       ret = btrfs_check_chunk_valid(root, leaf, chunk, logical);
+       if (ret)
+               return ret;
 
        read_lock(&map_tree->map_tree.lock);
        em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
@@ -6502,6 +6589,7 @@ int btrfs_read_sys_array(struct btrfs_root *root)
        u32 array_size;
        u32 len = 0;
        u32 cur_offset;
+       u64 type;
        struct btrfs_key key;
 
        ASSERT(BTRFS_SUPER_INFO_SIZE <= root->nodesize);
@@ -6516,7 +6604,7 @@ int btrfs_read_sys_array(struct btrfs_root *root)
        set_extent_buffer_uptodate(sb);
        btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
        /*
-        * The sb extent buffer is artifical and just used to read the system array.
+        * The sb extent buffer is artificial and just used to read the system array.
         * set_extent_buffer_uptodate() call does not properly mark all it's
         * pages up-to-date when the page is larger: extent does not cover the
         * whole page and consequently check_page_uptodate does not find all
@@ -6568,6 +6656,15 @@ int btrfs_read_sys_array(struct btrfs_root *root)
                                break;
                        }
 
+                       type = btrfs_chunk_type(sb, chunk);
+                       if ((type & BTRFS_BLOCK_GROUP_SYSTEM) == 0) {
+                               btrfs_err(root->fs_info,
+                           "invalid chunk type %llu in sys_array at offset %u",
+                                       type, cur_offset);
+                               ret = -EIO;
+                               break;
+                       }
+
                        len = btrfs_chunk_item_size(num_stripes);
                        if (cur_offset + len > array_size)
                                goto out_short_read;
@@ -6586,13 +6683,15 @@ int btrfs_read_sys_array(struct btrfs_root *root)
                sb_array_offset += len;
                cur_offset += len;
        }
-       free_extent_buffer(sb);
+       clear_extent_buffer_uptodate(sb);
+       free_extent_buffer_stale(sb);
        return ret;
 
 out_short_read:
        printk(KERN_ERR "BTRFS: sys_array too short to read %u bytes at offset %u\n",
                        len, cur_offset);
-       free_extent_buffer(sb);
+       clear_extent_buffer_uptodate(sb);
+       free_extent_buffer_stale(sb);
        return -EIO;
 }
 
@@ -6604,6 +6703,7 @@ int btrfs_read_chunk_tree(struct btrfs_root *root)
        struct btrfs_key found_key;
        int ret;
        int slot;
+       u64 total_dev = 0;
 
        root = root->fs_info->chunk_root;
 
@@ -6645,6 +6745,7 @@ int btrfs_read_chunk_tree(struct btrfs_root *root)
                        ret = read_one_dev(root, leaf, dev_item);
                        if (ret)
                                goto error;
+                       total_dev++;
                } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
                        struct btrfs_chunk *chunk;
                        chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
@@ -6654,6 +6755,28 @@ int btrfs_read_chunk_tree(struct btrfs_root *root)
                }
                path->slots[0]++;
        }
+
+       /*
+        * After loading chunk tree, we've got all device information,
+        * do another round of validation checks.
+        */
+       if (total_dev != root->fs_info->fs_devices->total_devices) {
+               btrfs_err(root->fs_info,
+          "super_num_devices %llu mismatch with num_devices %llu found here",
+                         btrfs_super_num_devices(root->fs_info->super_copy),
+                         total_dev);
+               ret = -EINVAL;
+               goto error;
+       }
+       if (btrfs_super_total_bytes(root->fs_info->super_copy) <
+           root->fs_info->fs_devices->total_rw_bytes) {
+               btrfs_err(root->fs_info,
+       "super_total_bytes %llu mismatch with fs_devices total_rw_bytes %llu",
+                         btrfs_super_total_bytes(root->fs_info->super_copy),
+                         root->fs_info->fs_devices->total_rw_bytes);
+               ret = -EINVAL;
+               goto error;
+       }
        ret = 0;
 error:
        unlock_chunks(root);